Many common medical devices perform the function of resecting tissue. Suction, supplied by an external vacuum source is often used to evacuate tissue from the operative site.
Medical devices which cut and evacuate tissue are used in a variety of procedures, including ear, nose, and throat surgery, gynecological surgery, spinal surgery, ophthalmic surgery, and many other applications. Depending on the procedure, the evacuated tissue may be collected for pathological analysis.
When applied to ear, nose, and throat surgery, tissue resecting devices are commonly referred to as microdebriders.
Tissue incision may be performed by either a rotating cutter (unidirectional or oscillating) or a reciprocating cutter. In the case of a rotating cutter, an electric motor is commonly used as the source of motion. In the case of a reciprocating cutter, motion may be produced by manual actuation, through a control such as a button or trigger, or powered actuation using pulsed or valved compressed air. Each of these power sources has distinct disadvantages when used to power a resecting medical device.
For example, when an electric motor is used to provide rotational motion of a cutter, the additional weight of the electric motor may cause operator fatigue. Wires from an external power supply are inconvenient to make the connections and it is inconvenient to have the wires attached to the device during use.
An electric motor increases the total cost of a device because of the relatively high cost of the motor itself and the cost of a power supply (in the case of an externally powered motor) or the cost of a recharging unit (when rechargeable batteries are used). The addition of electric motors makes sterilization of the device more difficult, e.g., because of the added mass to the device from the motors. Additionally, the presence of batteries reduces the sterilization options available to the manufacturer, due to the heat generated by certain sterilization techniques. The presence of batteries adds potentially toxic chemicals that present additional challenges related to toxicity, sterilization, and device disposal.
Medical devices that include electric motors are often made to be re-usable which requires a system for reprocessing the device. When using a manually actuated cutting device, the operator may experience fatigue from repeated actuations. Additionally, manual actuations can be performed only as quickly as the operator can actuate the cutter via mechanical input through a control and the time required to perform an adequate number of actuations may be excessive.
Electrically-powered microdebriders typically require an expensive capital investment in a power console that is separate from the handpiece. The capital cost of the power console, handpiece, and disposable blades makes procedures such as a nasal polypectomy and other procedures cost prohibitive in a doctor's clinic setting.
Existing microdebriders are typically built with a handle of the device in line with the shaft of the device, as a result, the handle and the operator's hand may interfere with an endoscope and/or the camera.
Existing microdebriders expose a cutting blade to the end of the device. This may be disadvantageous when the operator loses sight of the end of the device and accidentally cuts or damages structures that come into contact with it.
As a result of these limitations, it is impractical for Ear, Nose, and Throat physicians to remove nasal and sinus polyps or other tissue in an office or other setting using the current technology. Therefore, patients are left with the undesirable options of a course of steroid treatments to reduce the size of the polyps (with associated steroid side effects), removal of the polyps in an ambulatory surgery center (cost prohibitive and therefore rarely performed as a stand-alone procedure), or leaving the polyps untreated and dealing with the associated breathing obstruction.